# A056743 (b-file synthesized from sequence entry)
0 0
1 1
2 2
3 6
4 18
5 176
6 630
7 7710
8 27594
9 356960
10 18407808
11 69273666
12 3697909056
13 53630700752
14 204064589160
15 2992477516800
16 169917983040000
17 9770466930024800
18 37800705069076950
19 2202596295934991760